Prevalence of latent tuberculosis infection among healthcare workers in China as detected by two interferon-gamma release assays.

Healthcare workers in China have a high risk of tuberculosis infection. This study measured the prevalence of latent tuberculosis infection in 210 healthcare workers in a chest hospital in Harbin using two interferon-gamma release assays (IGRAs) [QuantiFERON(®)-TB Gold In-Tube (QFT-GIT) and A.TB] and the tuberculin skin test. Results from the IGRAs had moderate agreement with positivity rates of 76.5% (QFT-GIT) and 65.7% (A.TB) but <50% of subjects returned for tuberculin skin test readings. Risk of infection increased with patient exposure. IGRAs may be more useful than tuberculin skin test in monitoring tuberculosis infections in high risk environments.